LAS VEGAS (AP) ¿ Allegiant Air said on Wednesday its May traffic jumped 20 percent, helped by its niche of hauling leisure travelers from smaller U.S. cities.

Allegiant, a unit of Allegiant Travel Co., said it flew 406.1 million revenue passenger miles across its whole system. An RPM is one passenger flown one mile. That was up from 338 million RPMs in May 2008.

Its load factor, or the percentage of seats filled, rose to 88 percent from 87.2 percent.

Capacity rose 19 percent to 461.3 million available seat miles from 387.5 million.

Not counting charter flights, Allegiant said traffic rose 23.9 percent to 381.1 million miles flown by paying passengers.

Capacity rose 22.9 percent to 420.5 million available seat miles.

Its load factor rose to 90.6 percent from 89.9 percent.

Shares of the company, which flies travelers in small cities to leisure destinations, declined 82 cents to $43.55.

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